PM97867: DB2 10: INSERT PERFORMANCE ENHANCEMENT

A fix is available

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APAR status

Closed as new function.

Error description

Insert performance enhancement for DML activity pattern such as
insert and delete within the same commit scope in one-way data
sharing environment.
(d167243)

Local fix

Problem summary

****************************************************************
* USERS AFFECTED: All DB2 V10 for z/OS users of applications *
* that access Universal Table space (UTS) *
* with a data pattern of insert and *
* delete. *
****************************************************************
* PROBLEM DESCRIPTION: An application that accesses *
* Universal Table Space (UTS) could *
* result in high get page count if the *
* data accessing pattern consists of *
* inserts and deletes. *
****************************************************************
* RECOMMENDATION: *
****************************************************************
When deleted space distributes through the table space,
the subsequent insert process could result in high get page
count. This is due to the false lead threshold that was
increased to improve space reuse within the candidate segment
or during the exhaustive search prior to physical extend.
However, the extra page search does not fit for the situation
where the data page has unusable free space. As a result, the
get page count would increase by visiting more pages for each
search step.

Problem conclusion

Temporary fix

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* HIPER *
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Comments

DB2 code was changed to limit the threshold increase to
DSNDBD01 object only.